The Detroit Symphony Orchestra can boast some of the finest conductors and virtuosi in the world: Vladimir Ashkenazy conducts Mussorgsky's Pictures at an Exhibition this month and Itzhak Perlman, Pinchas Zukerman and the jazz maestro Herbie Hancock are all regular visitors. To that enviable list of luminaries must now be added probably the most singular figure ever to take to the stage at the DSO, or any other orchestra - step forward ASIMO!

The moment he entered the Max M. Fisher Music Centre on Tuesday night it was evident that this was to be no ordinary performance. For a start, there was his rather stilted gait and the fact that at 130cm (4ft 3 inches) his head rose in standing position barely above those of the seated musicians. And that's before considering his general appearance, which bears an uncanny resemblance to Neil Armstrong on that first moon landing, crossed with Lego Man.

ASIMO is a robot, and this was the world's first known example of a live orchestral performance conducted by a robot (as opposed to a robotic performance, of which there have been umpteen). He is the product of the engineering and computer wizards at Honda Motor Co, who have been working since 1986 to perfect a humanoid robot under the acronym Advance Step in Innovative Mobility.

In that time Honda has taught him to walk, run, climb stairs, talk and - as of this week - conduct. He had his first public outing in the US in 2002, when he rang the opening bell at the New York Stock Exchange. In the long run the company bills him as an answer to the ageing population time-bomb; he will act as a house-help for the aged and infirm.

So how did he do on Tuesday night conducting the orchestra as it played the appropriately quixotic Impossible Dream from the 1965 Broadway Man of La Mancha? Let's start with the positives. He kept the beat, marking time without a baton and even moving from three beats to six with admirable clarity.

Beyond that, he managed to put some expression into his conducting, moving his torso from violin section to cellos and back again, nodding his head at high points and clenching his fist to denote passion.

He also showed a command of the diplomatic side of the conductor's role, greeting the audience at the beginning with a "Hello everyone!" and commenting after the final bow that "It is absolutely thrilling to perform with the Detroit Symphony Orchestra. This is a magnificent concert hall." Honda is clearly planning his next career move as a politician.

But the downsides cannot go unmentioned. Larry Hutchinson, a bass player with the orchestra, said that though ASIMO's movements were remarkably human, it was a bit like being conducted by a metronome. There was no two-way feedback, as all the robot had been programmed to do was follow precisely the tempo set in an earlier, human rendition of the song conducted by one of the orchestra's directors.

"At one point there was a retard - the music slowed down," Hutchinson said. "ASIMO's gesture wasn't very clear to the orchestra and they fell out of time with him. A human would have adapted to that and fixed it right away."

You might add that there was also none of the ecstatic pogo jumping of the Venezuelan wunderkind Gustavo Dudamel. And what of musical soul? Think of the Latvian conductor Mariss Jansons - at the end of a symphony his face looks as though it is about to explode.

ASIMO remained unruffled and impenetrable behind his dark visor, the only change in mood displayed coming from the orchestra itself, whose movements were reflected in the glass.

"I'm really not too worried about the competition," said Leonard Slatkin who is scheduled, assuming there is no late switch towards ASIMO, to take over as the orchestra's music director in September. "It's a very sweet and adorable machine, but that's all it is. There's not going to be an academy where robots train to be conductors. It's not going to happen."

Critic's view: Waving, not conducting

It was only a matter of time. After walking and talking like a human, ASIMO, Honda's most ambitious robot, has become a conductor. Or rather, has achieved an impression of conducting. As all its gestures were copied from the Detroit orchestra's education director what really happened was the opposite of a performance: it was a simulacrum of an interpretation, a grotesque parody of that most profound, social, and complex of human activities: making music in an orchestra.

If you can make a collection of car parts and computers work with real musicians, what's the point of real conductors? Conducting looks like semaphore anyway, so if you could imitate the gestures of Wilhelm Furtwängler or Carlos Kleiber, you ought to be well on your way. If only it were that simple.

Even if you have spent hours mimicking your favourite maestros, nothing can prepare you for standing in front of a group of musicians. Conducting is about how you respond, trying to make players and singers perform the idealised version of the music you have in your head. It's all about the subtlety of that interaction, not hand signals.

Still, at least ASIMO could beat time. Perhaps if you transplanted ASIMO's unerring metronome into the skulls of young conductors, you would produce the perfect musician. Who knows: in a Honda lab somewhere, ASIMO von Karajan may well be taking shape.Tom Service

· Tom Service is a Guardian music critic, and is writing a book about conducting